Thread: Improving TD5 performance. exhaust query

Regarding EGT's should I also get temperature monitors fitted for EGT, just so I can know what is happening.
Do you know if the ceramic coating dissapates heat better/faster? What sort of $'s to get manifold coated?

I think that an EGT gauge is the most important gauge for a modified TD5. A boost gauge is helpful if you want to set and control boost above 15PSI.

Mine is fitted at the dimple on the exhaust mainfold just in front of the turbo.

I think it cost about $120 for the ceramic coating but I also think that it was a cheap price done in Wyong by Wyong Powder coaters.
The flatting of the manifold cost $100 and I dewebbed it and elongated the holes myself.
So far 40KK and no problems. I also fitted Mercedes studs with belleville washers .
The ceramic coating keeps the heat in the manifold and insulates the manifold from the exhaust gasses. It is primarily a reliability thing.

The EGT gauge is not just to know what is happening. It is a primary management device. when you have a modified motor you tend to drive by it up hills while towing. Even with no mods I think the EGTs would be excessive if you drove flat to the floor in a high gear. This was reinforced to me recently when I towed my daughter's camping trailer up a steep hill. the car was pulling well in locked third but the EGTs flew up to 750. I changed back to second and eased off and they dropped to 650.
Regards PhilipA

Originally Posted by vbrab

I'm looking to lift performance on 2003 TD5 D2.
Topic appears to have been done to death and I think I have a list of what I can do to improve performance.
Looking to do some towing, so just want to give engine its best chance to perform and to manage hills etc.

Intend to remove EGR, get ECU remapped, and if standard intercooler still isn't big enough, will have to look to change that also.

Looking to add SS extractors and also de-cat and remove centre muffler, by changing exhaust front pipe.
I see mention of putting 3" exhaust system to improve engine breathing.

QUERY
The outlet size on bottom of turbo exhaust flange is 60mm, so how do they marry up a 3" (75mm) exhaust pipe to that?
Does the exhaust person simply weld 3" pipe on to the old 60MM exhaust flange, and by virtue of the exhaust exiting into 75mm pipe, and by removing CAT and muffler, that allows it to breath better anyway?

Is there a ready to go 3" exhaust pipe option, or do they have to be made up by exhaust person?
I am in WA, so who might I look to in Perth if I have to get exhaust made to order? (any suggestions, my usual exhaust guy has retired).

Any other obvious things I should be doing to assist engine?

My thoughts, in modding an engine you should be working to keep the EGTs down. Larger intercoolers bring EGTs down and increase power, my thoughts are that they shouldn't be an "if needed", especially if the ECU tune is being altered for more power, which will increase EGTs. If something brings the EGTs up, something has to bring them down again so you don't have a hot engine that wont allow you to use the HP when towing or on highway hills.

Yep EGR, easy done.
Extractors, as in true extractors I've never seen for a Td5? Fabricated manifolds that I've seen I wouldnt have called extractors, but they sound good.

Exhaust, from what I understand, the biggest choke is in the flex on the down tube, the rest is ok. I've tried middle muffler in/out and noise was the only difference I could note. The only Td5 exhaust system that I've heard about that actually does make a tested real difference is the TaiwanXP system. I'm pretty sure it was DPL that tested it and raved about it and I think Tombie may have tested it also. It comes out of QLD but I've just seen Perth dealers.

Landrover Discovery TD5 Wagon - 4WD Performance Exhaust Upgrades

The transition in pipe size should blend sizes just after the turbo, it shouldn't step up, that wouldnt be incredibly crap design to do that. Manufacturers and builders go to a lot of lengths to port match to increase efficiency and power, a step in the exhaust system would be a big move in the opposite direction.

The bellows style flex is awful, only about 40mm diameter down the guts?
The later braided style flex is fine.

What I don't like about the stock system is that while it uses mandrel bends all the way through it steps down and drops to 60mm through the cat, muffler and resonator.
Not ideal.

And step ups aren't really a problem.

Race headers have used stepped pipes in primaries (or small expansion chambers) in specific spots to counter reversion wave timing and modify the torque curve for the last 30 years.

Not saying it's ideal in a dump pipe off a turbo, but the flow is so turbulent and expanding rapidly at that point after exiting the turbine I think it's a lot better than the restriction and turbulence induced by the bellows

What are your thoughts on an 3inch system with an high flow muffler? Enough for the turbo and no overspeed?

It's overkill but that's what I'm running with a high flow cat to provide a modicum of resistance as a precaution in case of overspeed.

If you're tuner takes into account you're running a big pipe it shouldn't be an issue

Originally Posted by vbrab

Do you know if the ceramic coating dissapates heat better/faster? What sort of $'s to get manifold coated?

There's ceramic coating and there's ceramic coating. About 6 years ago i paid $100 cash for mine, and it started flaking off about 6 months later. I couldn't be bothered taking it off again and fighting over it. Here in Vic there is a mob that specialises in hot rods, and their work is great. Can't comment on price, but I'd look for something like that where you are.

Be careful of the SS ones. Aside from the cracking issue already mentioned, they often don't fit on a Disco, as they foul on the AC compressor. Might be fine on a Deefer...

Originally Posted by johntins

There's ceramic coating and there's ceramic coating. About 6 years ago i paid $100 cash for mine, and it started flaking off about 6 months later. I couldn't be bothered taking it off again and fighting over it. Here in Vic there is a mob that specialises in hot rods, and their work is great. Can't comment on price, but I'd look for something like that where you are.

Be careful of the SS ones. Aside from the cracking issue already mentioned, they often don't fit on a Disco, as they foul on the AC compressor. Might be fine on a Deefer...

On that note, isuzurover had a 4BD1T manifold coated inside and out.
Can't remember the sequence of events, but Ben did a test on the exhaust and there was a stupid high concentration of ceramics in the particle count.
The coating was shedding big time.
When he heard I was probably going to do the TD5 he warned me about coating the inside.
I do think it comes down to who does it.